package com.hmdp.service.impl;

import cn.hutool.core.bean.BeanUtil;
import cn.hutool.core.bean.copier.CopyOptions;
import cn.hutool.core.lang.UUID;
import cn.hutool.core.util.RandomUtil;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.dto.LoginFormDTO;
import com.hmdp.dto.Result;
import com.hmdp.dto.UserDTO;
import com.hmdp.entity.User;
import com.hmdp.mapper.UserMapper;
import com.hmdp.service.IUserService;
import com.hmdp.utils.RedisConstants;
import com.hmdp.utils.RegexUtils;
import com.hmdp.utils.UserHolder;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.BeanUtils;
import org.springframework.data.redis.connection.BitFieldSubCommands;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;
import javax.servlet.http.HttpSession;

import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.TimeUnit;

import static com.hmdp.utils.RedisConstants.*;
import static com.hmdp.utils.SystemConstants.USER_NICK_NAME_PREFIX;

/**
 * <p>
 * 服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Slf4j
@Service
public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements IUserService {

    @Resource
    private StringRedisTemplate stringRedisTemplate;

    /**
     * 发送手机验证码
     */
    @Override
    public Result sendCode(String phone, HttpSession session) {

        if(RegexUtils.isPhoneInvalid(phone)){
            return Result.fail("手机格式错误！");
        }
        //符合，生成验证码
        String code = RandomUtil.randomNumbers(6);
        //保存验证码到redis,与手机号
        stringRedisTemplate.opsForValue().set(LOGIN_CODE_KEY + phone, code, LOGIN_CODE_TTL, TimeUnit.MINUTES);
        //发送验证码（模拟）
        log.debug("发送验证码成功！验证码：{}",code);
        //放回ok
        return  Result.ok();
    }

    /**
     * 登录功能
     * @param loginForm 登录参数，包含手机号、验证码；或者手机号、密码
     */
    @Override
    public Result login(LoginFormDTO loginForm, HttpSession session) {
        String phone = loginForm.getPhone();
        //1.校验手机号
        if(RegexUtils.isPhoneInvalid(phone)){
            return Result.fail("手机格式错误！");
        }
        //3.从redis获取验证码并校验
        String cacheCode = stringRedisTemplate.opsForValue().get(LOGIN_CODE_KEY + phone);
        String code = loginForm.getCode();
        if(cacheCode == null || !cacheCode.equals(code) ){
            //不一致，报错
            return Result.fail("验证错误");
        }
        //一致，根据手机号查询用户
        User user = query().eq("phone",phone).one();

        //3.判断用户是否存在
        if(user == null){
            //不存在，创建新用户
            user = createUserWithPhone(phone);
        }
        //保存用户到redis中
        //随机生成token
        String token = UUID.randomUUID().toString(true);
        //将User对象转化为hash
        UserDTO userDTO = BeanUtil.copyProperties(user, UserDTO.class);
        Map<String, Object> userMap = BeanUtil.beanToMap(userDTO, new HashMap<>(),
                CopyOptions.create()
                        .setIgnoreNullValue(true)
                        .setFieldValueEditor((fieldName,fieldValue) -> fieldValue.toString()));
        //存储
        String tokenKEY = LOGIN_USER_KEY + token;
        stringRedisTemplate.opsForHash().putAll(tokenKEY,userMap);
        //设置token有效期
        stringRedisTemplate.expire(tokenKEY,LOGIN_USER_TTL,TimeUnit.MINUTES);

        //返回token
        return Result.ok(token);
    }

    @Override
    public Result sign() {
        //1、获取当前登录的用户
        Long userId = UserHolder.getUser().getId();
        //2、获取日期
        LocalDateTime now = LocalDateTime.now();
        //3、拼接key
        String keySuffix = now.format(DateTimeFormatter.ofPattern(":yyyyMM"));
        String key = USER_SIGN_KEY + userId + keySuffix;
        //4、获取今天时本月的第几天
        int dayOfMonth = now.getDayOfMonth();
        //5、写入redis setbit key offset 1
        stringRedisTemplate.opsForValue().setBit(key,dayOfMonth-1   ,true);
        return Result.ok();
    }

    @Override
    public Result signCount() {
        //1、获取当前登录的用户
        Long userId = UserHolder.getUser().getId();
        //2、获取日期
        LocalDateTime now = LocalDateTime.now();
        //3、拼接key
        String keySuffix = now.format(DateTimeFormatter.ofPattern(":yyyyMM"));
        String key = USER_SIGN_KEY + userId + keySuffix;
        //4、获取今天时本月的第几天
        int dayOfMonth = now.getDayOfMonth();
        //5、获取到本月为止的所有签到记录，返回的是一个十进制数字 bitfield sign:1010:202507 get u16 0
        List<Long> result = stringRedisTemplate.opsForValue().bitField(
                key,
                BitFieldSubCommands.create().get(BitFieldSubCommands.BitFieldType.unsigned(dayOfMonth)).valueAt(0)
        );
        if (result == null || result.isEmpty()){
            return Result.ok(0);
        }
        Long num = result.get(0);
        if (num == null || num == 0){
            return Result.ok(0);
        }
        //6、循环遍历
        int count = 0;
        while (true){
            //6.1 让这个数与1进行与运算，得到最后一个bit位    判断这个bit位是否位0
            if ((num & 1) == 0){
                //未签到
                break;
            }else {
                //不为0，说明已签到，计数器+1
                count++;
            }
            //把数组右移一位，抛弃最后以为bit位，继续下一个bit位
            num >>>= 1;
        }
        
        return Result.ok(count);
    }

    private User createUserWithPhone(String phone) {
        User user = User.builder()
                .phone(phone)
                .nickName(USER_NICK_NAME_PREFIX + RandomUtil.randomString(10))
                .build();
        //数据库保存用户
        save(user);
        return user;
    }
}
